Is imaging of the brain necessary at diagnosis for cutaneous head and neck melanomas?

Objective: To evaluate the frequency of brain metastasis at the time of diagnosis for patients with cutaneous head and neck melanoma (CHNM). Methods: Patients in the Surveillance, Epidemiology, and End Results (SEER) database were included from 2010 to 2014 based on a diagnosis of CHNM using ICD O-3 histology codes and primary site location documentation. Patients were also included if they had a “yes” or “no” documented in the “Mets at Dx–Brain” category. Results: In this study, 46 out of 19,066 (0.2%) patients diagnosed with CHNM presented with brain metastasis at diagnosis. Of the 19,066 patients, 14,124 (74.1%) were male. Caucasian race was noted in 18,299 cases (96.0%). 16.8% of patients with AJCC 7 Stage IV/M1 CHNM had brain metastasis at the time of diagnosis as compared to 0% in Stage I-III/M0 lesions (p <.001). Conclusions and relevance: The 2018 NCCN guidelines recommend healthcare providers consider ordering a baseline brain MRI for patients with stage IIIC or greater melanoma. This study demonstrates the very low frequency of brain metastasis at time of diagnosis in patients with CHNM and supports the NCCN recommendations demonstrating that only very advanced stages of CHNM require baseline brain imaging.